package com.example.changetu;

import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends AppCompatActivity {
     private ImageView ivDog;
     private Button btnNext;
     private int[] dogImgs = {R.drawable.dog1,R.drawable.dog2,
             R.drawable.dog3,R.drawable.dog4,R.drawable.dog5,};
     private int index = 0;
     private Handler handler;
     private final int MSG_CHANGE_DOG = 1001;
     private Boolean isPause = true;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ivDog = findViewById(R.id.image_dog);
        btnNext = findViewById(R.id.btn_next);
        handler = new Handler(new Handler.Callback() {
            @Override
            public boolean handleMessage(Message message) {

                if(message.what == MSG_CHANGE_DOG){
                    index = (index+1)%dogImgs.length;
                    ivDog.setImageResource(dogImgs[index]);
                    return true;
                }
                return false;
            }
        });
        new Thread(new Runnable() {
            @Override
            public void run() {
                while (true){
                    try {
                        Thread.sleep(2000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    if(!isPause){
                        Message message = new Message();
                        message.what = MSG_CHANGE_DOG;
                        handler.sendMessage(message);
                        Log.e("MainActiy","send change message");
                    }
                }
            }
        }).start();
        btnNext.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {


                     if(isPause){
                         isPause = false;
                     }
                     else{
                         isPause=true;
                     }
                }

        });
    }
}
